JP2016150997A - Liquid polyisocyanate composition, curable polyurethane composition using the composition and optical mold member using the polyurethane composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a liquid polyisocyanate composition excellent in coloring prevention in time and workability or white turbidness prevention by normal temperature liquid and a curable polyurethane composition having long pot life sing the liquid polyisocyanate composition.SOLUTION: Reduction of coloring generated in time is achieved by blending a sulfur-containing phosphoric acid compound with organic polyisocyanate containing 2,4'-diphenylmethane diisocyanate or 2,2'-diphenylmethane isocyanate and further a curable polyurethane composition can prolong pot life by using the liquid polyisocyanate as a curing agent. The curable polyurethane composition can be used for an optical mod member because it is excellent in low coloring property and white turbidness prevention.SELECTED DRAWING: None

Description

  The present invention relates to a liquid polyisocyanate composition, a curable polyurethane composition using the composition, and an optical molded member using the polyurethane composition.

  Conventionally, urethane resins are widely used in various industrial applications as industrial products such as rolls and belts because they are excellent in mechanical properties such as wear resistance and impact resistance. In particular, in optical applications such as optical lenses and optical components, not only excellent optical properties but also impact resistance is required, and urethane resins applied to these applications are being studied.

  As a method for obtaining a cured product of a urethane resin, a polyisocyanate compound and an active hydrogen group-containing compound such as a polyol compound are mixed, poured into a mold, thermally cured, and then cooled and removed from the mold. There is known a reaction injection molding method or the like in which a mixed solution is poured into a mold while being pressed and cured by pressing and heating in a short time and taken out from the mold. The polyisocyanate compound used here has a very high reactivity of the isocyanate group, so it thickens in a short time after mixing, and when molding becomes cloudy due to poor molding or self-polymerization of the polyisocyanate compound was there.

Against this background, various methods have been tried to ensure moldability (pot life) for a certain period of time after mixing the polyisocyanate compound and the active hydrogen group-containing compound.
As a specific method for imparting these pot life properties, the following method (1) or (2) has been proposed.
(1) A method for adjusting acidity (an acid component that is liberated by reacting with alcohol or water) when a polyisocyanate compound is produced or after the production thereof is added (for example, Patent Document 1 or Patent) Reference 2).
(2) A method of adding aromatic-containing sulfonic acid or acidic phosphate ester to a polyisocyanate compound (for example, Patent Documents 3 to 6).

JP 2006-273717 A JP 2009-114258 A JP-A-9-087239 JP-A-10-121031 JP 2006-089556 A WO2014 / 080749

  Against this background, in recent years, polyisocyanate compounds used where transparency is required, such as for optical materials, have been demanded to suppress coloring over time, workability, and longer pot life. Yes. However, in the polyisocyanate compound to which the additive proposed in the prior art is added, a certain effect was seen in pot life properties, but it is a problem to achieve both suppression of coloring over time and further extension of pot life. It was. In addition, development of a polyisocyanate compound that is liquid at room temperature has been desired in order to suppress white turbidity of the molded product.

  The present invention has been made on the basis of the above circumstances, and is a liquid polyisocyanate composition excellent in workability and white turbidity suppression because of coloration over time, long pot life, and liquidity at room temperature. And a curable polyurethane composition using the composition.

  As a result of repeated investigations, the present inventors have formulated a sulfur-containing phosphoric acid compound into diphenylmethane diisocyanate containing 2,4′-diphenylmethane diisocyanate or 2,2′-diphenylmethane diisocyanate, so that the optical molding member can also be used. A liquid polyisocyanate composition excellent in suppression of coloring over time that can be used is obtained, and further, by using this liquid polyisocyanate composition, a curable polyurethane composition excellent in workability and white turbidity suppression is obtained. The present invention has been found.

That is, the present invention is shown in the following [1] to [6].
[1] An organic polyisocyanate (A) and a sulfur-containing phosphate compound (B) containing at least one selected from a compound represented by the following general formula (1) and a compound represented by the general formula (2) In the polyisocyanate composition,
The organic polyisocyanate (A) contains at least one selected from 2,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate in a total amount of 50 to 99% by mass,
The sulfur-containing phosphoric acid compound (B) is contained in an amount of 0.01 to 3% by mass in the polyisocyanate composition.
A liquid polyisocyanate composition characterized by the above.

(R1 to R3 in General Formula (1) and General Formula (2) each represent an independent alkyl group having 1 to 18 carbon atoms.)
[2] The liquid polyisocyanate composition according to [1], wherein the organic polyisocyanate (A) is diphenylmethane diisocyanate.
[3] A curable polyurethane comprising the liquid polyisocyanate composition according to any one of [1] or [2] and an active hydrogen group-containing compound (C) having two or more active hydrogen groups. Composition.
[4] The number of active hydrogen groups in one molecule of the active hydrogen group-containing compound (C) is in the range of 2 to 4, and the number average molecular weight is in the range of 750 to 50,000. ] The curable polyurethane composition of description.
[5] In the curable polyurethane composition, the hindered amine compound (D) is added in an amount of 0.1 to 100 parts by weight with respect to 100 parts by weight of the total amount of the liquid polyisocyanate composition and the active hydrogen group-containing compound (C). The curable polyurethane composition according to any one of [3] or [4], comprising 3 parts by weight.
[6] An optical molded member obtained from the curable polyurethane composition according to any one of [3] to [5].

  According to the liquid polyisocyanate composition of the present invention and the curable polyurethane composition using the composition, sulfur-containing phosphorus is added to diphenylmethane diisocyanate containing 2,4′-diphenylmethane diisocyanate or 2,2′-diphenylmethane diisocyanate. By blending the acid compound, coloration with time can be reduced, and furthermore, by using this liquid polyisocyanate as a curing agent, a curable urethane composition capable of extending the pot life can be obtained. Since this curable polyurethane composition is excellent in low colorability and white turbidity suppression, it can be used for an optical molding member.

The liquid polyisocyanate composition of the present invention comprises at least an organic polyisocyanate (A) and a sulfur-containing phosphoric acid compound (B). In the organic polyisocyanate (A), 2,4′-diphenylmethane diisocyanate and Containing at least one selected from 2,2′-diphenylmethane diisocyanate in a total amount of 50 to 99 mass%,
The sulfur-containing phosphoric acid compound (B) is a polyisocyanate composition that is liquid at room temperature and contains 0.01 to 3% by mass in the polyisocyanate composition.
Here, normal temperature is in accordance with JIS Z8703 (standard state of test place) and means 20 ° C. ± 15 ° C.

<Organic polyisocyanate (A)>
The organic polyisocyanate (A) used in the liquid polyisocyanate composition of the present invention will be described. Examples of the organic polyisocyanate include aromatic polyisocyanates, araliphatic polyisocyanates, aliphatic polyisocyanates, alicyclic polyisocyanates, sulfur atom-containing polyisocyanates, and the like. Among them, aromatic polyisocyanate can be preferably used in the present invention, and diphenylmethane diisocyanate can be more preferably used.

  Here, diphenylmethane diisocyanate will be described in more detail.

  In general, diphenylmethane diisocyanate is 4,4'-diphenylmethane diisocyanate bonded at the para-para position, 2,4'-diphenylmethane diisocyanate bonded at the para-ortho position, and 2,2 'bonded at the ortho-ortho position. -Consists of three isomers of diphenylmethane diisocyanate. The ratio of the isomers can be quantified by a known method by gas chromatography.

  The organic polyisocyanate (A) used in the liquid polyisocyanate composition of the present invention has a total amount of 2,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate, which is an isomer of diphenylmethane diisocyanate, of 50 to 50. 99 mass% should just be contained, and the remaining 1-50 mass% is comprised by 4,4'- diphenylmethane diisocyanate etc., and there is no special prescription | regulation in the isomer ratio. In the present invention, the total amount of 2,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate in the organic polyisocyanate (A) is 50 to 99% by mass, so that it is liquid at normal temperature. This makes it possible to provide workability during molding and suppression of cloudiness.

The industrial production method of diphenylmethane diisocyanate is not particularly limited as long as the total amount of 2,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate falls within the specified range. Is manufactured through the following three steps.
(1) A polyamine containing diaminodiphenylmethane as a main component is obtained by a condensation reaction between aniline and formaldehyde.
(2) A polyphenylmethane polyisocyanate containing diphenylmethane diisocyanate as a main component is obtained by reacting this polyamine with phosgene.
(3) Diphenylmethane diisocyanate is obtained from polyphenylmethane polyisocyanate by fractional distillation.

  In addition, the isomer distribution of polyphenylmethane polyisocyanate is determined by the condensation reaction in the first stage, and in this condensation reaction, a binuclear body, a trinuclear body, and a polynuclear body are simultaneously generated. Here, the dinuclear compound is diphenylmethane diisocyanate containing the above-mentioned three kinds of isomers having two benzene rings in one molecule obtained by reacting 2 mol of aniline and 1 mol of formaldehyde. Is a compound having 3 benzene rings in one molecule obtained by reaction of 3 mol of aniline and 2 mol of formaldehyde, and a polynuclear substance is one having 4 or more benzene rings in one molecule. The ratio of the binuclear body, the trinuclear body, and the polynuclear body can be measured by known gel permeation chromatography (GPC).

  In addition, a known polyisocyanate compound or polyisothiocyanate compound can be used in combination as long as the performance is not deteriorated. Known polyisocyanate compounds include aromatic polyisocyanates, araliphatic polyisocyanates, aliphatic polyisocyanates, alicyclic polyisocyanates, sulfur atom-containing polyisocyanates, these isocyanurate-modified polyisocyanates, uretdione-modified polyisocyanates, urethanes. Examples thereof include modified polyisocyanate, burette-modified polyisocyanate, uretonimine-modified polyisocyanate, and acylurea-modified polyisocyanate.

<Aromatic polyisocyanate>
Specific examples of the aromatic polyisocyanate include 4,4′-diphenylmethane diisocyanate, 2,4′-diphenylmethane diisocyanate, 2,2′-diphenylmethane diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diisocyanate, 4,4′-diphenyl ether diisocyanate, 2-nitrodiphenyl-4,4′-diisocyanate, 2,2′-diphenylpropane-4,4′-diisocyanate, 3,3′-dimethyldiphenylmethane-4,4′-diisocyanate, 4,4′-diphenylpropane diisocyanate, m-phenylene diisocyanate, p-phenylene diisocyanate, naphthylene-1,4-diisocyanate, naphthylene-1,5-diisocyanate, 3,3′-dimethoxydiphenyl-4 4'-diisocyanate, and the like can be given.

<Aromatic aliphatic polyisocyanate>
Specific examples of the araliphatic polyisocyanate include 1,3- or 1,4-xylylene diisocyanate or a mixture thereof, 1,3- or 1,4-bis (1-isocyanato-1-methylethyl) benzene or a mixture thereof. Examples thereof include a mixture, ω, ω′-diisocyanato-1,4-diethylbenzene, and the like.

<Aliphatic polyisocyanate>
Specific examples of the aliphatic polyisocyanate include hexamethylene diisocyanate, tetramethylene diisocyanate, 2-methylpentane-1,5-diisocyanate, 3-methylpentane-1,5-diisocyanate, lysine diisocyanate, trioxyethylene diisocyanate, ethylene diisocyanate. , Trimethylene diisocyanate, octamethylene diisocyanate, nonamethylene diisocyanate, 2,2'-dimethylpentane diisocyanate, 2,2,4-trimethylhexane diisocyanate, decamethylene diisocyanate, butene diisocyanate, 1,3-butadiene-1,4-diisocyanate 2,4,4-trimethylhexamethylene diisocyanate, 1,6,11-undecane triisocyanate, , 3,6-hexamethylene triisocyanate, 1,8-diisocyanate-4-isocyanate methyloctane, 2,5,7-trimethyl-1,8-diisocyanate-5-isocyanate methyloctane, bis (isocyanate ethyl) carbonate, bis (Isocyanate ethyl) ether, 1,4-butylene glycol dipropyl ether-α, α′-diisocyanate, lysine diisocyanate methyl ester, 2-isocyanate ethyl-2,6-diisocyanate hexanoate, 2-isocyanate propyl-2,6 -Diisocyanate hexanoate etc. can be mentioned.

<Alicyclic polyisocyanate>
Specific examples of the alicyclic polyisocyanate include isophorone diisocyanate, cyclohexyl diisocyanate, bis (isocyanate methyl) cyclohexane, dicyclohexylmethane diisocyanate, methylcyclohexane diisocyanate, dicyclohexyldimethylmethane diisocyanate, 2,2′-dimethyldicyclohexylmethane diisocyanate, bis (4 -Isocyanate-n-butylidene) pentaerythritol, hydrogenated dimer acid diisocyanate, 2-isocyanatemethyl-3- (3-isocyanatepropyl) -5-isocyanatemethylbicyclo [2.2.1] heptane, 2-isocyanatemethyl-3 -(3-isocyanatopropyl) -6-isocyanatomethylbicyclo [2.2.1] heptane, 2 -Isocyanatomethyl-2- (3-isocyanatopropyl) -5-isocyanatomethylbicyclo [2.2.1] heptane, 2-isocyanatomethyl-2- (3-isocyanatopropyl) -6-isocyanatomethylbicyclo [2.2 .1] Heptane, 2-isocyanatomethyl-3- (3-isocyanatopropyl) -5- (2-isocyanatoethyl) bicyclo [2.2.1] heptane, 2-isocyanatomethyl-3- (3-isocyanatopropyl) -6- (2-isocyanatoethyl) bicyclo [2.2.1] heptane, 2-isocyanatomethyl-2- (3-isocyanatopropyl) -5- (2-isocyanatoethyl) bicyclo [2.2.1] heptane 2-isocyanate methyl-2- (3-isocyanate pro ) -6- (2-isocyanatoethyl) bicyclo [2.2.1] heptane, 2,5-bis (isocyanatemethyl) bicyclo [2.2.1] heptane hydrogenated diphenylmethane diisocyanate, norbornane diisocyanate, hydrogenated tri Examples thereof include range isocyanate, hydrogenated xylene diisocyanate, and hydrogenated tetramethylxylene diisocyanate.

<Sulfur atom-containing polyisocyanate>
Specific examples of the sulfur atom-containing polyisocyanate include thiodiethylene diisocyanate, thiodipropyl diisocyanate, thiodihexyl diisocyanate, dimethyl sulfone diisocyanate, dithiodimethyl diisocyanate, dithiodiethyl diisocyanate, dithiodipropyl diisocyanate, diphenyl sulfide-2,4′-diisocyanate. , Diphenyl sulfide-4,4′-diisocyanate, 3,3′-dimethoxy-4,4′-diisocyanate dibenzylthioether, bis (4-isocyanatomethylphenyl) sulfide, 4,4′-methoxyphenylthioethylene glycol-3 , 3′-diisocyanate, diphenyl disulfide-4,4′-diisocyanate, 2,2′-dimethyldiphenyl disulfide-5 5′-diisocyanate, 3,3′-dimethyldiphenyl disulfide-5,5′-diisocyanate, 3,3′-dimethyldiphenyl disulfide-6,6′-diisocyanate, 4,4′-dimethyldiphenyl disulfide-5,5 ′ -Diisocyanate, 3,3'-dimethoxydiphenyl disulfide-4,4'-diisocyanate, 4,4'-dimethoxydiphenyl disulfide-3,3'-diisocyanate, diphenylsulfone-4,4'-diisocyanate, diphenylsulfone-3, 3′-diisocyanate, benzidine sulfone-4,4′-diisocyanate, diphenylmethanesulfone-4,4′-diisocyanate, 4-methyldiphenylsulfone-2,4′-diisocyanate, 4,4′-dimethoxydiphenylsulfone-3, 3'-Gii Socyanate, 3,3′-dimethoxy-4,4′-diisocyanate benzyldisulfone, 4,4′-dimethyldiphenylsulfone-3,3′-diisocyanate, 4,4′-di-tert-butyldiphenylsulfone-3,3 '-Diisocyanate, 4,4'-methoxyphenylethylenesulfone-3,3'-diisocyanate, 4,4'-dicyclodiphenylsulfone-3,3'-diisocyanate, 4-methyl-3-isocyanatophenylsulfonyl-4' -Isocyanate phenol ester, 4-methoxy-3-isocyanatophenylsulfonyl-4'-isocyanate phenol ester, 4-methyl-3-isocyanatophenylsulfonylanilide-3'-methyl-4'-isocyanate, diphenylsulfonylethylenediamine-4,4 ' Diisocyanate, 4,4′-methoxyphenylsulfonylethylenediamine-3,3′-diisocyanate, 4-methyl-3-isocyanatophenylsulfonylanilide-4-methyl-3′-isocyanate, thiophene-2,5-diisocyanate, 1, Examples include 4-dithian-2,5-diisocyanate.
<Polyisothiocyanate compound>
Specific examples of the polyisothiocyanate compound include 1,2-diisothiocyanate ethane, 1,3-diisothiocyanate propane, 1,4-diisothiocyanate butane, 1,6-diisothiocyanate hexane, P-phenylene diene. Isopropylidene diisothiocyanate, cyclohexane diisothiocyanate, 1,2-diisothiocyanate benzene, 1,3-diisothiocyanate benzene, 1,4-diisothiocyanate benzene, 2,4-diisothiocyanate toluene, 2,5 -Diisothiocyanate-m-xylene, 4,4-diisothiocyanate-1,1'-biphenyl, 1,1'-methylenebis (4-isothiocyanatebenzene), 1,1'-methylenebis (4-isothiocyanate- 2-methylbenzene), 1,1'-me Tylene bis (4-isothiocyanate-3-methylbenzene), 1,1 ′-(1,2-ethanediyl) bis (4-isothiocyanate benzene), 4,4′-diisothiocyanate benzophenone, 4,4′-di Isothiocyanate-3,3'-dimethylbenzophenone, benzanilide-3,4'-diisothiocyanate, diphenyl ether-4,4'-diisothiocyanate, diphenylamine-4,4'-diisocyanate, 2,4,6-triiso Thiocyanate-3,5-triazine, hexanedioyl diisothiocyanate, nonanedioyl diisothiocyanate, carbonic diisothiocyanate, 1,3-benzenecarbonyldiisothiocyanate, 1,4-benzenecarbonyldiisothiocyanate, (2,2 '-Bipyridine)- , 4′-dicarbonyldiisothiocyanate, thiobis (3-isothiocyanatepropane), thiobis (2-isothiocyanateethane), dithiobis (2-isothiocyanateethane), 1-isothiocyanate-4-[(2-isocyanate) [Sulfonyl] benzene, thiobis (4-isothiocyanatebenzene), sulfonylbis (4-isothiocyanatebenzene), sulfinylbis (4-isothiocyanatebenzene), dithiobis (4-isothiocyanatebenzene), 4-isothiocyanate-1- [ (4-Isocyanatophenyl) sulfonyl] -2-methoxybenzene, 4-methyl-3-isothiocyanate benzenesulfonyl-4′-isocyanate phenyl ester, 4-methyl-3-isothiocyanate benzene Sulfonylanilide-3'-methyl-4'-isocyanate, thiophenone-2,5-diisothiocyanate, 1,4-dithiane-2,5-diisothiocyanate, 1-isocyanate-3-isothiocyanate propane, 1-isocyanate- 5-isothiocyanate pentane, 1-isocyanate-6-isothiocyanate hexane, isothiocyanate carbonyl isocyanate, 1-isocyanate-4-isothiocyanate cyclohexane, 1-isocyanate-4-isothiocyanate benzene, 4-methyl-3-isothiocyanate- 1-isothiocyanate benzene, 2-isocyanate-4,6-diisothiocyanate-1,3,5-triazine, 4-isothiocyanate-4′-isothiocyanate diphenyl sulfide, - it can be mentioned isothiocyanate 2'isothiocyanate diethyl disulfide and the like.

  Next, the sulfur-containing phosphoric acid compound (B) blended with the organic polyisocyanate (A) will be described.

<Sulfur-containing phosphoric acid compound (B)>
The sulfur-containing phosphoric acid compound (B) of the present invention is represented by the following general formula (1) or general formula (2), and can impart an extended pot life by blending with the organic polyisocyanate (A). .

  R1 to R3 in the general formula (1) and the general formula (2) each represent an independent alkyl group having 1 to 18 carbon atoms, and from the viewpoint of pot life, storage stability, and white turbidity suppression, the carbon number is 8-13 are preferable. When the number of carbons exceeds the upper limit, there is a risk of becoming cloudy with a decrease in compatibility.

  Specific examples of the alkyl group having 1 to 18 carbon atoms include methyl group, ethyl group, n-propyl group, isopropyl group, n-butyl group, isobutyl group, tert-butyl group, pentyl group, cyclopentane group, Hexyl, cyclohexyl, heptyl, octyl, 2-ethylhexyl, trimethylhexyl, nonyl, decyl, undecyl, dodecyl, tridecyl, tetradecyl, octadecyl, heptadecyl, hexadecyl, oleyl And a straight chain, branched chain, or alicyclic alkyl group.

  Specific examples of the compound represented by the general formula (1) include dimethyldithiophosphoric acid, diethyldithiophosphoric acid, diisopropyldithiophosphoric acid, dibutyldithiophosphoric acid, di-2-ethylhexyldithiophosphine. Dialkyldithiophosphoric acid such as foliacid, diisodecyl dithiophosphoric acid, dilauryl dithiophosphoric acid, didecyl dithiophosphoric acid, distearyl dithiophosphoric acid, dioleyl dithiophosphoric acid These can be used alone or in combination of two or more.

  Specific examples of the compound represented by the general formula (2) include trimethylthiophosphite, triethylthiophosphite, triisopropylthiophosphite, tributylthiophosphite, tri-2-ethylhexylthiophosphite, triisodecyl. Examples include trialkylthiophosphites such as thiophosphite, trilauryl thiophosphite, tridecyl thiophosphite, tristearyl thiophosphite, trioleyl thiophosphite, and these can be used alone or in combination of two or more. .

  As a compounding quantity of the sulfur-containing phosphoric acid compound (B) of this invention, the polyisocyanate composition contains 0.01-3 mass%, and is compatible with the effect of long pot life improvement and coloring suppression with time. can do. If it is less than the lower limit, the pot life is not sufficient, and there is a risk of white turbidity due to poor workability and some reaction variations. Moreover, when exceeding an upper limit, there exists a possibility of coloring with time.

  Since the combined use of the sulfur-containing phosphoric acid compound (B) of the present invention with conventionally proposed adjustment of acidity, acidic phosphoric acid ester, etc. may cause a decrease in pot life, the sulfur-containing phosphoric acid compound It is preferable to use (B) alone.

  The liquid polyisocyanate composition thus obtained can be used as a curing agent for a curable polyurethane composition obtained by reaction with the active hydrogen group-containing compound (C).

<Active hydrogen group-containing compound (C)>
The active hydrogen group-containing compound (C) used in the curable polyurethane composition of the present invention is not particularly limited as long as it contains at least two active hydrogen groups in the structure. Ether polyols, polycarbonate polyols, polyolefin polyols, acrylic polyols, silicone polyols, castor oil-based polyols, fluorine-based polyols, transesterification products of two or more polyols, and hydroxyl-terminated prepolymers urethanated with polyisocyanates can be used. These can be used alone or as a mixture of two or more.

  Moreover, a well-known polythiol compound can also be used and a thiourethane resin can be obtained by reaction.

<Polyester polyol>
Specific examples of polyester polyols include phthalic acid, isophthalic acid, terephthalic acid, naphthalenedicarboxylic acid, succinic acid, tartaric acid, oxalic acid, malonic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, glutaconic acid, azelaic acid, Dicarboxylic acids such as sebacic acid, 1,4-cyclohexyl dicarboxylic acid, α-hydromuconic acid, β-hydromuconic acid, α-butyl-α-ethylglutaric acid, α, β-diethylsuccinic acid, maleic acid, fumaric acid, etc. Or one or more of these anhydrides and the like, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, -Nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene glycol, neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, One or more low molecular weight polyols having a molecular weight of 500 or less, such as dimer acid diol, bisphenol A ethylene oxide and propylene oxide adducts, bis (β-hydroxyethyl) benzene, xylylene glycol, glycerin, trimethylolpropane, pentaerythritol And those obtained from the polycondensation reaction. Also, lactone polyester polyols obtained from ring-opening polymerization of cyclic ester (so-called lactone) monomers such as ε-caprolactone, alkyl-substituted ε-caprolactone, δ-valerolactone, and alkyl-substituted δ-valerolactone can be exemplified. Furthermore, a polyester-amide polyol obtained by replacing a part of the low molecular polyol with a low molecular polyamine such as hexamethylene diamine, isophorone diamine, monoethanolamine, or a low molecular amino alcohol can also be used.

<Polyether polyol>
Specific examples of the polyether polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5 -Pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene glycol, Neopentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, bisphenol A, bis (β-hydroxyethyl) benzene, xylylene glycol, glycerin, trimethylolpropane, pentaerythritol, etc. Low molecular polio Or compounds having 2 or more, preferably 2 to 3 active hydrogen groups such as low molecular weight polyamines such as ethylenediamine, propylenediamine, toluenediamine, metaphenylenediamine, diphenylmethanediamine, and xylylenediamine As an agent, polyether polyols obtained by addition polymerization of alkylene oxides such as ethylene oxide, propylene oxide and butylene oxide, alkyl glycidyl ethers such as methyl glycidyl ether, aryl glycidyl ethers such as phenyl glycidyl ether, tetrahydrofuran A polyether polyol obtained by ring-opening polymerization of a cyclic ether monomer such as

<Polycarbonate polyol>
Specific examples of the polycarbonate polyol include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,5- Pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,9-nonanediol, 3-methyl-1,5-pentanediol, 3,3-dimethylolheptane, diethylene glycol, dipropylene glycol, neo Pentyl glycol, cyclohexane-1,4-diol, cyclohexane-1,4-dimethanol, dimer acid diol, ethylene oxide or propylene oxide adduct of bisphenol A, bis (β-hydroxyethyl) benzene, xylylene glycol, glycerin, Trimethi At least one low-molecular polyol such as propane propane and pentaerythritol, dialkyl carbonates such as dimethyl carbonate and diethyl carbonate, alkylene carbonates such as ethylene carbonate and propylene carbonate, diphenyl carbonate, dinaphthyl carbonate, dianthryl carbonate, diphen Mention may be made of those obtained from dealcoholization reactions and dephenol reactions with diaryl carbonates such as nantril carbonate, diindanyl carbonate and tetrahydronaphthyl carbonate.
Moreover, the polyol obtained by transesterification of polycarbonate polyol, polyester polyol, and low molecular polyol can also be used suitably.

<Polyolefin polyol>
Specific examples of the polyolefin polyol include polybutadiene having two or more hydroxyl groups, hydrogenated polybutadiene, polyisoprene, hydrogenated polyisoprene and the like.

<Acrylic polyol>
As an acrylic polyol, acrylic acid ester or methacrylic acid ester (hereinafter referred to as (meth) acrylic acid ester) and an acrylic acid hydroxy compound or methacrylic acid hydroxy compound having at least one hydroxyl group in the molecule that can be a reaction site Examples thereof include those obtained by copolymerizing an acrylic monomer by using heat energy, light energy such as ultraviolet rays or electron beams, and the like (hereinafter referred to as a (meth) acrylic acid hydroxy compound) and a polymerization initiator.

<(Meth) acrylic acid ester>
Specific examples of (meth) acrylic acid esters include alkyl esters having 1 to 20 carbon atoms. Specific examples of such (meth) acrylate esters include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, (Meth) acrylic such as hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, octyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, dodecyl (meth) acrylate Mention of (meth) acrylic acid alicyclic alcohols such as alkyl alkyl esters, cyclohexyl (meth) acrylates, (meth) acrylic acid aryl esters such as phenyl (meth) acrylate and benzyl (meth) acrylate Can do. Such (meth) acrylic acid esters can be used alone or in combination of two or more.

<(Meth) acrylic acid hydroxy compound>
Specific examples of the (meth) acrylic acid hydroxy compound have at least one hydroxyl group in the molecule that can be a reaction point with the polyisocyanate (B), specifically, 2-hydroxyethyl acrylate, Acrylic acid hydroxy compounds such as 2-hydroxypropyl acrylate, 4-hydroxybutyl acrylate, 3-hydroxy-2,2-dimethylpropyl acrylate, and pentaerythritol triacrylate are listed. Moreover, methacrylic acid hydroxy compounds, such as 2-hydroxyethyl methacrylate, 2-hydroxypropyl methacrylate, 4-hydroxybutyl methacrylate, 3-hydroxy-2,2-dimethylpropyl methacrylate, and pentaerythritol trimethacrylate, are mentioned. These acrylic acid hydroxy compounds and methacrylic acid hydroxy compounds can be used alone or in combination of two or more.

<Silicone polyol>
Specific examples of the silicone polyol include a vinyl group-containing silicone compound obtained by polymerizing γ-methacryloxypropyltrimethoxysilane and the like, and α, ω-dihydroxypolydimethylsiloxane having at least one terminal hydroxyl group in the molecule, α, Mention may be made of polysiloxanes such as ω-dihydroxypolydiphenylsiloxane.

<Castor oil-based polyol>
Specific examples of the castor oil-based polyol include linear or branched polyester polyols obtained by the reaction of castor oil fatty acid and polyol. Dehydrated castor oil, partially dehydrated castor oil partially dehydrated, and hydrogenated castor oil added with hydrogen can also be used.

<Fluorine-based polyol>
Specific examples of the fluorine-based polyol include linear or branched polyols obtained by a copolymerization reaction using a fluorine-containing monomer and a monomer having a hydroxy group as essential components. Here, the fluorine-containing monomer is preferably a fluoroolefin, for example, tetrafluoroethylene, chlorotrifluoroethylene, trichlorofluoroethylene, hexafluoropropylene, vinylidene fluoride, vinyl fluoride, trifluoromethyl trifluoroethylene. Is mentioned. Examples of the monomer having a hydroxyl group include hydroxyalkyl vinyl ethers such as hydroxyethyl vinyl ether, 4-hydroxybutyl vinyl ether and cyclohexanediol monovinyl ether, hydroxyalkyl allyl ethers such as 2-hydroxyethyl allyl ether, and vinyl hydroxyalkyl crotonates. Examples thereof include monomers having a hydroxyl group such as a hydroxyl group-containing vinyl carboxylate or an allyl ester.

<Polythiol compound>
Specific examples of the polythiol compound include methanedithiol, 1,2-ethanedithiol, 1,1-propanedithiol, 1,2-propanedithiol, 1,3-propanedithiol, 2,2-propanedithiol, 1,6- Hexanedithiol, 1,2,3-propanetrithiol, 1,1-cyclohexanedithiol, 1,2-cyclohexanedithiol, 2,2-dimethylpropane-1,3-dithiol, 3,4-dimethoxybutane-1,2 -Dithiol, 2-methylcyclohexane-2,3-dithiol, bicyclo [2,2,1] pepta-exo-cis-2,3-dithiol, 1,1-bis (mercaptomethyl) cyclohexane, bis (thiomalate) (2 -Mercaptoethyl ester), 2,3-dimercaptosuccinic acid (2-mercap) Ethyl ester), 2,3-dimercapto-1-propanol (2-mercaptoacetate), 2,3-dimercapto-1-propanol (3-mercaptoacetate), diethylene glycol bis (2-mercaptoacetate), diethylene glycol bis (3- Mercaptopropionate), 1,2-dimercaptopropyl methyl ether, 2,3-dimercaptopropyl methyl ether, 2,2-bis (mercaptomethyl) -1,3-propanedithiol, bis (2-mercaptoethyl) Ether, ethylene glycol bis (2-mercaptoacetate), ethylene glycol bis (3-mercaptopropionate), trimethylolpropane tris (2-mercaptoacetate), trimethylolpropane tris (3-mercapto Lopionate), pentaerythritol tetrakis (2-mercaptoacetate), pentaerythritol tetrakis (3-mercaptopropionate), 1,2-bis (2-mercaptoethylthio) -3-mercaptopropane), 1,2-dimercapto Benzene, 1,3-dimercaptobenzene, 1,4-dimercaptobenzene, 1,2-bis (mercaptomethyl) benzene, 1,3-bis (mercaptomethyl) benzene, 1,4-bis (mercaptomethyl) benzene 1,2-bis (mercaptoethyl) benzene, 1,3-bis (mercaptoethyl) benzene, 1,4-bis (mercaptoethyl) benzene, 1,2-bis (mercaptomethyleneoxy) benzene, 1,3- Bis (mercaptomethyleneoxy) benzene, 1,4-bis (me Lucaptomethyleneoxy) benzene, 1,2-bis (mercaptoethyleneoxy) benzene, 1,3-bis (mercaptoethyleneoxy) benzene, 1,4-bis (mercaptoethyleneoxy) benzene, 1,2,3-tri Mercaptobenzene, 1,2,4-trimercaptobenzene, 1,3,5-trimercaptobenzene, 1,2,3-tris (mercaptomethyl) benzene, 1,2,4-tris (mercaptomethyl) benzene, 1 , 3,5-tris (mercaptomethyl) benzene, 1,2,3-tris (mercaptoethyl) benzene, 1,2,4-tris (mercaptoethyl) benzene, 1,3,5-tris (mercaptoethyl) benzene 1,2,3-tris (mercaptomethyleneoxy) benzene, 1,2,4-tris (mercapto) Tyleneoxy) benzene, 1,3,5-tris (mercaptomethyleneoxy) benzene, 1,2,3-tris (mercaptoethyleneoxy) benzene, 1,2,4-tris (mercaptoethyleneoxy) benzene, 1,3, 5-tris (mercaptoethyleneoxy) benzene, 1,2,3,4-tetramercaptobenzene, 1,2,3,5-tetramercaptobenzene, 1,2,4,5-tetramercaptobenzene, 1,2, 3,4-tetrakis (mercaptomethyl) benzene, 1,2,3,5-tetrakis (mercaptomethyl) benzene, 1,2,4,5-tetrakis (mercaptomethyl) benzene, 1,2,3,4-tetrakis (Mercaptoethyl) benzene, 1,2,3,5-tetrakis (mercaptoethyl) benzene, 1,2,4 5-tetrakis (mercaptoethyl) benzene, 1,2,3,4-tetrakis (mercaptoethyl) benzene, 1,2,3,5-tetrakis (mercaptomethyleneoxy) benzene, 1,2,4,5-tetrakis ( Mercaptomethyleneoxy) benzene, 1,2,3,4-tetrakis (mercaptoethyleneoxy) benzene, 1,2,3,5-tetrakis (mercaptoethyleneoxy) benzene, 1,2,4,5-tetrakis (mercaptoethylene) Oxy) benzene, 2,2′-dimercaptobiphenyl, 4,4′-dimercaptobiphenyl, 4,4′-dimercaptobibenzyl, 2,5-toluenedithiol, 3,4-toluenedithiol, 1,4- Naphthalenedithiol, 1,5-naphthalenedithiol, 2,6-naphthalenedithiol, 2 , 7-naphthalenedithiol, 2,4-dimethylbenzene-1,3-dithiol, 4,5-dimethylbenzene-1,3-dithiol, 9,10-anthracene dimethanethiol, 1,3-di (p-methoxy) Phenyl) propane-2,2-dithiol, 1,3-diphenylpropane-2,2-dithiol, phenylmethane-1,1-dithiol, 2,4-di (p-mercaptophenyl) pentane, 2,5-dithiol Chlorobenzene-1,3-dithiol, 1,3-di (p-chlorophenyl) propane-2,2-dithiol, 3,4,5-tribromo-1,2-dimercaptobenzene, 2,3,4,6- Tetrachloro-1,5-bis (mercaptomethyl) benzene, 2-methylamino-4,6-dithiol-sym-triazine, 2-ethylamino-4 6-dithiol-sym-triazine, 2-amino-4,6-dithiol-sym-triazine, 2-morpholino-4,6-dithiol-sym-triazine, 2-cyclohexylamino-4,6-dithiol-sym-triazine 2-methoxy-4,6-dithiol-sym-triazine, 2-phenoxy-4,6-dithiol-sym-triazine, 2-thiobenzeneoxy-4,6-dithiol-sym-triazine, 2-thiobutyloxy -4,6-dithiol-sym-triazine, 1,2-bis (mercaptomethylthio) benzene, 1,3-bis (mercaptomethylthio) benzene, 1,4-bis (mercaptomethylthio) benzene, 1,2-bis ( Mercaptoethylthio) benzene 1,3-bis (mercaptoethylthio) , 1,4-bis (mercaptoethylthio) benzene, 1,2,3-tris (mercaptomethylthio) benzene, 1,2,4-tris (mercaptomethylthio) benzene, 1,3,5-tris (mercaptomethylthio) ) Benzene, 1,2,3-tris (mercaptoethylthio) benzene, 1,2,4-tris (mercaptoethylthio) benzene, 1,3,5-tris (mercaptoethylthio) benzene, 1,2,3 , 4-Tetrakis (mercaptomethylthio) benzene, 1,2,3,5-tetrakis (mercaptomethylthio) benzene, 1,2,4,5-tetrakis (mercaptomethylthio) benzene, 1,2,3,4-tetrakis ( Mercaptoethylthio) benzene, 1,2,3,5-tetrakis (mercaptoethylthio) benzene, 1,2,4,5-tetrakis (mercaptoethylthio) benzene, bis (mercaptomethyl) sulfide, bis (mercaptoethyl) sulfide, bis (mercaptopropyl) sulfide, bis (mercaptomethylthio) methane, bis (2-mercaptoethyl) Thio) methane, bis (3-mercaptopropyl) methane, 1,2-bis (mercaptomethylthio) ethane, 1,2- (2-mercaptoethylthio) ethane, 1,2- (3-mercaptopropyl) ethane, 1 , 3-bis (mercaptomethylthio) propane, 1,3-bis (2-mercaptoethylthio) propane, 1,3-bis (3-mercaptopropylthio) propane, 1,2,3-tris (mercaptomethylthio) propane 1,2,3-tris (2-mercaptoethylthio) propa 1,2,3-tris (3-mercaptopropylthio) propane, tetrakis (mercaptomethylthiomethyl) methane, tetrakis (2-mercaptoethylthiomethyl) methane, tetrakis (3-mercaptopropylthiomethyl) methane, bis (2 , 3-dimercaptopropyl) sulfide, 2,5-dimercapto-1,4-dithiane, 2,5-bis (mercaptomethyl) -1,4-dithiane, bis (mercaptomethyl) disulfide, bis (mercaptoethyl) disulfide Bis (mercaptopropyl) disulfide, hydroxymethyl sulfide bis (2-mercaptoacetate), hydroxymethyl sulfide bis (3-mercaptopropionate), hydroxyethyl sulfide bis (2-mercaptoacetate), hydroxy Tyl sulfide bis (3-mercaptopropionate), hydroxypropyl sulfide bis (2-mercaptoacetate), hydroxypropyl sulfide bis (3-mercaptopropionate), hydroxymethyl disulfide bis (2-mercaptoacetate), hydroxymethyl disulfide Bis (3-mercaptopropionate), hydroxyethyl disulfide bis (2-mercaptoacetate), hydroxyethyl disulfide bis (3-mercaptopropionate), hydroxypropyl disulfide bis (2-mercaptoacetate), hydroxypropyl disulfide bis ( 3-mercaptopropionate), 2-mercaptoethyl ether bis (2-mercaptoacetate), 2-mercaptoethyl ether bis (3 -Mercaptopropionate), 1,4-dithian-2,5-diol bis (2-mercaptoacetate), 1,4-dithian-2,5-diol bis (3-mercaptopropionate), bis (thioglycolate) ( 2-mercaptoethyl ester), thiodipropionic acid bis (2-mercaptoethyl ester), 4,4-thiodibutyric acid bis (2-mercaptoethyl ester), dithiodiglycolic acid bis (2-mercaptoethyl ester), dithiodi Propionic acid bis (2-mercaptoethyl ester), 4,4-dithiodibutyric acid bis (2-mercaptoethyl ester), thiodiglycolic acid bis (2,3-dimercaptopropyl ester), thiodipropionic acid bis (2 , 3-Dimercaptopropyl ester), dithioglycolic acid bi (2,3-dimercaptopropyl ester), dithiodipropionic acid (2,3-dimercaptopropyl ester), 3,4-thiophenedithiol, 2,5-dimercapto-1,3,4-thiadiazole Can do.

  The number of active hydrogen groups (average functional group number) in one molecule of the active hydrogen group-containing compound (C) used is in the range of 2.0 to 4.0, and the number average molecular weight is 750 to 50,000. It is preferable to be in the range. If it is out of these ranges, the durability and impact resistance may be reduced.

  The proportion of the polyisocyanate composition and the active hydrogen group-containing compound (C) is not particularly limited, but the isocyanate group and the active hydrogen group-containing compound (C) in the polyisocyanate composition are not particularly limited. It is preferable to blend so that the molar ratio of the active hydrogen groups in the mixture is 0.5 to 1.5 in terms of R = isocyanate group / active hydrogen group. Outside these ranges, durability and impact resistance may be reduced.

<Hindered amine compound (D)>
In the curable polyurethane composition, a hindered amine compound (D) can be used in combination as a light stabilizer. Specific examples of the hindered amine compound (D) include commercially available products such as Lowiite 76 (manufactured by Chemtura), LowiIite 92 (manufactured by Chemtura), Tinuvin 144 (manufactured by BASF), Tinuvin 292 (manufactured by BASF), Tinuvin 765 (manufactured by BASF). ADEKA STAB LA-52 (manufactured by ADEKA), ADEKA STAB LA-72 (manufactured by ADEKA), JF-95 (manufactured by Johoku Chemical Industry Co., Ltd.), etc., or a combination of these two or more. Can be used.

  The amount of the hindered amine compound added is preferably 0.1 to 3 parts by weight based on 100 parts by weight of the total amount of the polyisocyanate composition and the active hydrogen group-containing compound (C). By mix | blending in these ranges, the molding excellent in hue is obtained.

  Further, an additive can be used as long as the performance is not deteriorated. Additives include lubricants, plasticizers, hydrolysis inhibitors, antioxidants, UV absorbers, pigments, dyes, fillers, antistatic agents, flame retardants, antiblocking agents, dispersants, catalysts, storage stabilizers. Etc. can be suitably blended.

<Method of molding curable polyurethane composition>
Next, a method for molding the curable polyurethane composition will be described.
As a molding method of the curable polyurethane composition of the present invention, an active hydrogen group-containing compound (C) is added to a polyisocyanate composition in which an organic polyisocyanate (A) and a sulfur-containing phosphate compound (B) are prepared in advance. Step (1) for obtaining a curable polyurethane composition by mixing, step (2) for casting the curable polyurethane composition into a mold, polymerization of the curable polyurethane composition is started, And a step (3) of polymerization.

<Step (1)>
In the case of using an isocyanate compound other than diphenylmethane diisocyanate as the organic polyisocyanate (A), considering the solubility of the sulfur-containing phosphate compound (B), the sulfur-containing phosphate compound (B) is dissolved in diphenylmethane diisocyanate, It is preferable to mix other isocyanate compounds with the mixed solution. Thereby, the expression of the stable pot life property, the cloudiness of a molding, etc. can be suppressed.
Moreover, it is preferable to perform the temperature at the time of mixing with a polyisocyanate composition and an active hydrogen group containing compound (C) at 30 degrees C or less, when the suppression of the reactivity of a polyisocyanate composition and workability | operativity are considered.

<Step (2)>
In the casting process, the curable polyurethane composition of the present invention is injected into a molding mold (mold) held by a gasket or tape, and if necessary, defoaming treatment or pressurization under reduced pressure, It is preferable to perform filtration such as decompression.

<Step (3)>
In this step, polymerization of the curable urethane composition cast in the molding mold is started, and the composition is polymerized. The temperature at which the polymerization is started is preferably 30 ° C. or less in order to improve the mold releasability of the molded product after polymerization and to suppress problems such as white turbidity in the obtained molded product. The polymerization conditions are not limited because the conditions vary greatly depending on the isocyanate to be used, the type of the active hydrogen group-containing compound (C), the shape of the mold, etc., but are carried out at about 0 to 140 ° C. for 1 to 48 hours.

  Regarding the method of adding the additive, the preparation procedure differs depending on the component of the polyisocyanate composition and the type and blending ratio of the active hydrogen group-containing compound (C), and is not generally limited. It is appropriately selected in consideration of operability, safety, convenience and the like.

  The molded product obtained by reacting the curable polyurethane composition of the present invention may be subjected to a treatment such as annealing as necessary, and the treatment temperature is usually in the range of 50 to 150 ° C.

  Moreover, you may give a coating layer to the surface of the molding obtained in this way on one side or both surfaces as needed. Examples of the coating layer include a primer layer, a hard coat layer, an antireflection film layer, an antifogging coat film layer, an antifouling layer, and a water repellent layer. These coating layers may be used as a single layer or a multilayer of two or more layers.

  The curable polyurethane composition of the present invention thus obtained can be molded in various shapes by changing the mold during casting polymerization. Since this molded product has no coloration or white turbidity and is excellent in transparency, it is an optical molding member for plastic lenses, camera lenses, light emitting diodes (LEDs), prisms, optical fibers, information recording substrates, filters, light emitting diodes, and the like. Preferably used.

  Examples of the present invention will be described below, but the present invention is not limited to these examples.

<Preparation of polyisocyanate composition>
<Example 1>
100 g of diphenylmethane diisocyanate (MDI-1, NCO content: 33.8% by mass, manufactured by Tosoh Corporation) having a total content of 2,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate of 95% by mass, 0.1 g of (2-ethylhexyl) dithiophosphoric acid (trade name: Phoslex DT-8, manufactured by SC Organic Chemical Co., Ltd.) was mixed and dissolved at 20 ° C. to obtain the liquid polyisocyanate composition NCO-1 of the present invention. .
The liquid polyisocyanate composition NCO-1 was liquid at room temperature, and no suspended matter or the like accompanying mixing was observed.

<Examples 2-7 and Comparative Examples 1-7>
The materials shown in Table 1 and Table 2 were mixed and dissolved in the same manner as in Example 1 to obtain a polyisocyanate composition. Comparative Example 4 was prepared by dissolving at 60 ° C. because MDI-3 was a solid.

Abbreviations of materials used in Table 1 and Table 2 are as follows.
(1) MDI-1: diphenylmethane diisocyanate having a total content of 2,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate of 95% by mass (manufactured by Tosoh Corporation)
(2) MDI-2: Diphenylmethane diisocyanate having a total content of 2,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate of 55% by mass (manufactured by Tosoh Corporation)
(3) MDI-3: diphenylmethane diisocyanate having a total content of 2,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate of 1% by mass (manufactured by Tosoh Corporation)
(4) HDI: hexamethylene diisocyanate (5) Phoslex DT-8: di (2-ethylhexyl) dithiophosphoric acid (manufactured by SC Organic Chemical Co., Ltd.)
(6) DTPDE: Diethyldithiophosphoric acid (manufactured by Tokyo Chemical Industry Co., Ltd.)
(7) Phoslex S-230: Trialkylthiophosphate (C12 alkyl group: C13 alkyl group = 1: 1, manufactured by SC Organic Chemical Co., Ltd.)
(8) JP-508: 2-ethylhexyl acid phosphate (manufactured by Johoku Chemical Industry Co., Ltd.).

As shown in Tables 1 and 2, the liquid polyisocyanate composition to which the sulfur-containing phosphoric acid compound was added was able to reduce coloring compared to the comparative example, and no occurrence of suspended matters was observed.
Moreover, about the pot life, the liquid polyisocyanate composition which added the sulfur-containing phosphoric acid compound was able to extend about 15 to 120 minutes compared with the comparative example 1 which has not added the additive.

<Adjustment of curable polyurethane composition and molded body>
<Example 8>
A homogeneous solution was prepared by mixing and dissolving 73 g of a propylene oxide adduct (trade name: GP-1000, manufactured by Sanyo Kasei Kogyo Co., Ltd.) with 0.4 g of a light stabilizer (TINUVIN292, manufactured by BASF) as an initiator. Next, 27 g of NCO-1 was added and mixed at 20 ° C. so that the molar ratio of isocyanate group to hydroxyl group was NCO group / OH group = 1, and defoaming was performed at 400 Pa to obtain a curable polyurethane composition. It was adjusted. Thereafter, it was poured into a molding mold, put into a curing oven, and gradually heated from 15 ° C. to 120 ° C. over 24 hours to be cured. After the curing, the product was taken out from the oven and released from the mold. The releasability was good and no mold peeling was observed. The obtained molded body was further annealed at 120 ° C. for 2 hours. The appearance of the obtained molded product was transparent, and no defects such as cloudiness were observed.

<Examples 9 to 14 and Comparative Examples 8 to 14>
Except having changed the polyisocyanate composition, the curable polyurethane composition was prepared by the method similar to Example 8, and the molding was obtained through the hardening process. Table 3 shows the appearance of the molded product.

(1) Evaluation test 1:
<Number of colors>
The initial value of the prepared polyisocyanate composition and the colorability when left for 1 week under the condition of 50 ° C. were evaluated by Hazen units according to JIS K0071-1.

(2) Evaluation test 2:
<Pot life>
The prepared curable polyurethane composition was allowed to stand at 20 ° C., and the time when the reaction rate of the isocyanate group reached 20% was measured. The reaction rate was determined by measuring the residual isocyanate group of the curable polyurethane composition by titration, and the reaction rate (%) = [initial isocyanate group content (mol) −residual isocyanate group content (mol)] / initial. It calculated by isocyanate group content (mol) x100.

(3) Evaluation test 3:
<Appearance of molded product>
The presence or absence of cloudiness was evaluated visually.
<Evaluation criteria>
・ Transparent: Pass (Evaluation: ○)
・ Partly cloudy, cloudy: rejected (evaluation: x)

Claims (6)

Polyisocyanate composition comprising organic polyisocyanate (A) and sulfur-containing phosphoric acid compound (B) containing at least one compound selected from the compound represented by the following general formula (1) and the compound represented by general formula (2) In things,
The organic polyisocyanate (A) contains at least one selected from 2,4′-diphenylmethane diisocyanate and 2,2′-diphenylmethane diisocyanate in a total amount of 50 to 99% by mass,
The sulfur-containing phosphoric acid compound (B) is contained in an amount of 0.01 to 3% by mass in the polyisocyanate composition.
A liquid polyisocyanate composition characterized by the above.

(R1 to R3 in General Formula (1) and General Formula (2) each represent an independent alkyl group having 1 to 18 carbon atoms.) The liquid polyisocyanate composition according to claim 1, wherein the organic polyisocyanate (A) is diphenylmethane diisocyanate. A curable polyurethane composition comprising the liquid polyisocyanate composition according to claim 1 and an active hydrogen group-containing compound (C) having two or more active hydrogen groups. 4. The number of active hydrogen groups in one molecule of the active hydrogen group-containing compound (C) is in the range of 2 to 4, and the number average molecular weight is in the range of 750 to 50,000. Curable polyurethane composition. In the curable polyurethane composition, the hindered amine compound (D) is added in an amount of 0.1 to 3 parts by weight based on 100 parts by weight of the total amount of the liquid polyisocyanate composition and the active hydrogen group-containing compound (C). The curable polyurethane composition according to claim 3, wherein the curable polyurethane composition is contained. An optical molding member obtained from the curable polyurethane composition according to claim 3.